Don't get a z3-style fender. If you do find one, it will almost certainly be made of fiberglass. Instead, find some at salvage yard (most have part requests online) and get those cheap, and simply ad in the vent with the actual vent part available at bav auto.
<span style='color:gray'><span style='font-family:Courier'>1995 e36 3 Series RIP
1999 e46 3 Series BURN IN HELL
2000 MR-S Roadster= Current</span></span>